FIG. 1 depicts telecommunications system 100 comprising originating telecommunications terminal 101 (e.g., a wireless telephone, a wireline telephone, a personal digital assistant [PDA], etc.), terminating telecommunications terminal 105, data-processing system 102 (e.g., a switch, a router, a private branch exchange [PBX], etc.), data-processing system 104, and network 103 (e.g., the Public Switched Telephone Network [PSTN], the Internet, a cellular wireless network, etc.) in accordance with the prior art. Telecommunications terminal 101 is capable of placing calls (e.g., voice calls, video calls, text messaging sessions, etc.) to other telecommunications terminals, and telecommunications terminal 105 is capable of receiving calls from other telecommunications terminals. When telecommunications terminal 101 places a call to telecommunications terminal 105, the call is set up via data-processing system 102, network 103, and data-processing system 104, as described below and with respect to FIG. 2.
FIG. 2 depicts a message-flow diagram for the placing of a call from telecommunications terminal 101 to telecommunications terminal 105. In this call scenario, telecommunications terminal 101 is known as the originating terminal, and telecommunications terminal 105 is known as the terminating terminal. Similarly, data-processing system 102 is known as the originating data-processing system, and data-processing system 104 is known as the terminating data-processing system.
At event 201, originating terminal 101 transmits a call-origination signal to originating data-processing system 102 via network 103.
At event 202, originating data-processing system 102 receives the call origination signal.
At event 203, originating data-processing system 102 allocates one or more resources for the call. For example, if originating data-processing system 102 is a router, it might allocate a route in its route table and associate the route with the call. If originating data-processing system 102 is a switch, it might allocate a trunk, and associate the trunk with the call.
At event 204, originating data-processing system 102 transmits a call-setup signal to terminating data-processing system 104 via network 103.
At event 205, terminating data-processing system 104 receives the call-setup signal.
At event 206, terminating data-processing system 104 allocates one or more resources for the call.
At event 207, terminating data-processing system 104 transmits an acknowledgment to originating data-processing system 102 via network 103.
At event 208, originating data-processing system 102 receives the acknowledgment transmitted at event 207.
At event 209, terminating data-processing system 104 generates a ringback signal. The ringback is intended to let the user of originating terminal 101 know that terminating terminal 105 is alerting its user of the incoming call (i.e., that terminal 105 is “ringing”).
At event 210, terminating data-processing system 104 transmits the ringback signal to originating data-processing system 102 via network 103.
At task 211, originating data-processing system 102 receives the ringback signal.
At task 212, originating data-processing system 102 transmits the ringback signal to originating terminal 101, which receives the ringback at task 213. The ringback signal is typically a periodic “ringing” sound. The ringback signal continues to “ring” until the call is answered (e.g., when the user of terminal 105 answers the call, when a voice mail system answers the call, etc.) or until the user of originating terminal 101 decides to end the attempted call (i.e., “hangs up”).
In parallel with tasks 211 and 212, terminating data-processing system 104 transmits at task 214 a ringtone to terminating terminal 105, and terminating terminal 105 receives the ringtone at task 215. The ringtone notifies the user of terminal 105 of the arrival of a call (e.g., via a “ringing” sound, via a tune, etc.).
Some wireless telecommunications service providers offer a premium ringback service to their subscribers, in which the subscriber can associate with their phone a particular ringback (e.g., a song, a sequence of tones, etc.) that will be played to the calling party whenever the subscriber is called on the associated phone. As an option, the subscriber can also associate a different ringback with each of several calling party numbers that the subscriber identifies when programming the ringback service.
Customizable ringbacks have become a popular feature with teenagers in some countries (e.g., Republic of Korea, etc.) because of its “cool factor” and because it enables subscribers to express their individuality. Telecommunications service providers also find such ringback services desirable because they are able to collect additional fees for the service, and they can lure customers away from service providers that do not offer the service. Furthermore, customizable ringbacks can potentially improve what callers experience while waiting for the called subscribers to answer the calls.